On Sunday evening , July 19th , I observed groups of Am. Robins flying to their communal roost at Cromwell Valley Park in Baltimore County.  Because they were traveling due south I thought they might be the start of early migration, so I began to count them as they passed overhead.  The count lasted from 7:40 pm to 8:25 pm and totalled more than 900 birds.  The Robins were in small groups, flying at tree-top level, and I saw many descending into the valley at the Christmas tree farm.  Clearly these birds were coming into roost, and I later learned that this is common behavior for Robins as the breeding season winds down.  I may keep a close eye on this behavior and try to ascertain when migration actually begins for Robins.  I remember seeing many thousands of Robins migrating here last summer/fall ( was it mid to late August ? ) and this year I hope to record my observations concerning this most well known bird.

Jim Meyers
Cromwell Valley Park
Parkville Md